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Name _____________________________________
Date ____________
Work & Power Problems
Work
Fill-in-the-blank:
1. ___________________ is done when an object moves through a distance because of a
________________ acting upon the object.
2. When calculating work, you should use the formula: work = force X ____________________.
3. The SI unit for work is the _______________________. It is represented by the letter ______.
Work Problems:
4. F = 90 N
d=5m
W=?
________
________
________
5. F = 6 N
W = 72 J
d=?
________
________
________
6. W = 120 J
d = 24 m
F=?
7. W = ?
F = 62.6 N
d = 13 m
________
________
________
8. W = 13.2 J
F=2N
d=?
________ 9. W = 136 J
________
d = 27.2 m
________
F=?
________
________
________
________
________
________
10. If 360 Joules of work are needed to move a crate a distance of 4 meters, what is the weight of the
crate?
11. If a group of workers can apply a force of 1000 Newtons to move a crate 20 meters, what amount
of work will they have accomplished?
12. If 68 Joules of work were necessary to move a 4 Newton crate, how far was the crate moved?
13. How much work is done in holding a 15 N sack of potatoes while waiting in line at the grocery
store for 3 minutes.
14. If 150 Joules of work is needed to move a box 10 meters, what force was used?
II. Power
Fill-in-the-blank:
1. _________________________________ is the rate at which work is done.
2. When calculating power, you should use the formula P = _________________ divided by
_____________. In this formula, “P” stands for power, ____ stands for work, and _____ for time.
3. The SI unit for Power is the ______________________.
C. Power Problems
4. W = 100 J
t = 10 s
P=?
________
________
________
5. W = 225 J
P = 25 W
t=?
_______
_______
_______
6. P = 20 W
t = 15 s
W=?
________
________
________
7. W = 500 J
t = 25 s
P=?
________
________
________
8. W = 336 J
t=?
P = 14 W
_______
_______
_______
9. W = ?
t = 16.6 s
P = 64 W
________
________
________
10. A person weighing 600 N gets on an elevator. The elevator lifts the person 6 m in 10 seconds. How
much power was used?
11. How much time is needed to produce 720 Joules of work if 90 watts of power is used?
12. If 68 W of power is produced in 18 seconds, how much work is done?
13. A set of pulleys lifts an 800 N crate 4 meters in 7 seconds. What power was used?
14. If a man moves a large box that weighs 10 Newtons 20 meters in 30 seconds, how much power
was used?
Work and Power problems
1. A force of 825N is needed to push a car across a lot. Two students push the car 35m. How much work is done?
2. A delivery person carries a 34N package from the ground floor to the fifth floor, a total of 15m. How much work is
done by the delivery person?
3. What work is done by a forklift raising a 583kg box 1.2m?
4. A sailor pulls a boat along the dock using a rope at an angle of 60° with the horizon. How much work is done if he
exerts a force of 225N on the rope and pulls the boat 30m?
5. You pull a box at an angle of 46°. You use 6,543.68J to move a box 15m across the floor. How much force must be
applied to complete this task?
6. A box that weighs 575N is lifted a distance of 20m straight up by a rope. The job is done in 10s. What amount of
power in watts and kilowatts?
(Watts) ___________________________
(Kilowatts) ___________________________
7. An elevator lifts a total mass of 1400kg a distance of 30m in 11s. How much power does the elevator generate?